Myths pervade most aspects of life and they can be very persistent. Whether it’s “we only use 10% of our brain” or “George Washington had wooden teeth” these myths can be relatively harmless – or they can really get in the way of true understanding and action.
Historic preservation has its own set of myths. Some originate from a grain of truth, many are outright wrong, and still others require a more nuanced understanding.
I run across these myths all the time in our work where we often push back with education, persuasion, and our own experiences. In this series of short essays, we take on the four most persistent and sometimes damaging myths about historic preservation in the Adirondacks. (This is the third of a four part series. You can find the second part here.)
MYTH #3: Historic buildings are hopelessly energy inefficient and cannot meet current demands for sustainability.
No myth in historic preservation is further from the truth. Yes – most newly constructed buildings use less energy compared to existing and historic buildings BUT existing buildings can be made to be competitively energy efficient and meet the current New York State Energy Code. This is typically done by first understanding the energy characteristics of your building through an energy audit and then systematically making conservation improvements that might include adding insulation and storm windows, stopping air infiltration, and replacing conventional heating and cooling systems with heat pumps.
But there’s something else we should consider in looking at the new versus existing question. All the energy to make the materials that went into an existing building has already been spent, sometimes hundreds of years ago. This we call embodied energy. In contrast, new buildings require a great deal of new energy to produce the concrete, bricks, gypsum, framing, roofing, and mechanical systems needed. These energy costs include the energy required to get the raw materials out of the ground or off the land, to transport the raw materials to the place of processing, to process the raw materials into a manufactured product, to transport the finished product to retailers and then to the consumer, and then to install the finished components into the building. All of these energy costs can be calculated and, for instance, an average-sized new house “consumes” about 181,000 kilowatts in energy before the house is ever occupied.
Assuming the new house is more energy efficient than an existing house, this means it will take an average of 40 years for an energy efficient new house to recover the energy and carbon expended in the construction of that house (Empty Homes Agency, 2008). We all want to live in more energy efficient buildings but, in making good decisions, it helps to understand both the energy consumed in operating a building AND the energy consumed in making a building. Add to this the fact that existing buildings CAN often be rehabilitated and improved to be as energy efficient as new construction and this puts the reuse of existing buildings in a new, much more favorable light.
Christine Bush and Nolan Cool contributed to this essay.